Laboratoire dynamique de la lithosphère et genèse de ressources minérales et énergétiques, Université Cadi Ayyad, Faculté des Sciences Semlalia, Av Abdelkrim Khattabi, B.P. 511 – 40000, Marrakech, Morocco
The Jebilets and Guemassa hercynian massives constitute one of the most important metallogenic provinces of Morocco. In this province, mining exploration is focused on the research of massive sulphide mineralization in a volcano-sedimentary sitting. It makes extensive use of geophysical methods performed on both ground airborne surveys. Magnetometry is one of the most employed techniques which show that magnetic anomalies are associated with pyrrhotite-rich massive sulphide. Indeed, the effectiveness of this method is proven by the discovery of the Hajar deposit through airborne magnetic survey. However, its use is handicapped by the abundance of basic and ultrabasic rocks that generate the same anomalies than massive sulphide ore bodies. This article is concerned with the magnetic prospecting difficulties related to mining exploration in the Jebilet-Guemassa metallogenic province. It clarifies the origin of magnetic anomalies related to basic and ultrabasic rocks enriched in iron-titanic minerals and suggests an alternative approach to bring response elements to this problem. This result may guide the mining exploration for the detection and characterization of anomalies associated with massive sulphide deposits in the geological and mining sitting of Jebilets-Guemassa.